DE102018118694A1 - laser diode chip - Google Patents

Abstract

A laser diode chip is described, comprising an n-type semiconductor region (3), a p-type semiconductor region (5) and an active layer (4) arranged between the n-type semiconductor region (3) and the p-type semiconductor region (5) ), an n-contact (9) and a p-contact (8), - at least one heating element (14), which are arranged on a side of the laser diode chip facing the p-type semiconductor region (5), the heating element (14) acts as a resistance heater.

Description

The invention relates to a laser diode chip, which is characterized in particular by an improved stability of the emission wavelength.

Laser diode chips usually have a temperature-dependent emission wavelength. Furthermore, production-related scattering of the emission wavelength can occur at a given temperature. This can be particularly undesirable for applications in measurement technology, e.g. if ambient light is to be filtered out by spectrally narrow-band filters in order to increase the signal / noise ratio of the measured value. When using these narrow-band filters, there is a risk that the wavelength of the laser light lies outside the transmission window of the filter, at least at certain temperatures, and therefore the light cannot reach the detector. This risk is particularly great if the laser diode chip e.g. Depending on the application, it cannot be used in a temperature-controlled environment or if the laser is to be operated at different powers (and therefore also at different levels of self-heating).

A possible solution is to temper the area around the laser. However, a larger mass must be heated for this, which requires high (peak) heating outputs, especially if the target wavelength is to be reached in a short time. In addition, with large heated masses, it is difficult to keep the temperature stable at the target value, since both the self-heating of the laser during operation and any rapid changes in the outside temperature have to be compensated for.

One problem to be solved is to provide an improved laser diode chip, which is particularly characterized by an improved stability of the emission wavelength.

This object is achieved by a laser diode chip according to independent claim 1. Advantageous refinements and developments of the invention are the subject of the dependent claims.

According to at least one embodiment, the laser diode chip comprises an n-type semiconductor region, a p-type semiconductor region and an active layer arranged between the n-type semiconductor region and the p-type semiconductor region. The n-type semiconductor region, the p-type semiconductor region and / or the active layer can each comprise one or more semiconductor layers. The laser diode chip has, for example, a p-contact for electrical contacting of the p-type semiconductor region and an n-contact for electrical contacting of the n-type semiconductor region. The p-contact and / or the n-contact can in particular have a metal, a metal alloy and / or a layer made of a transparent conductive oxide.

The laser diode chip can in particular have a III-V semiconductor material. Depending on the emission wavelength, the semiconductor material can be, for example, an arsenide compound semiconductor material, a phosphide compound semiconductor material or a nitride compound semiconductor material.

According to at least one embodiment, the laser diode chip comprises a heating element which is preferably arranged on a side of the laser diode chip facing the p-type semiconductor region. In particular, viewed from the active layer, the heating element follows the p-type semiconductor region. The heating element can, for example, be arranged directly on the p-type semiconductor region or preferably on an electrically insulating layer which is arranged on the p-type semiconductor region.

Here and in the following, the fact that a layer or an element is arranged or applied “on” or “above” another layer or another element means that the layer or the element is directly in direct mechanical and / or electrical contact on the other Layer or the other element is arranged. Furthermore, it can also mean that the one layer or the one element is arranged indirectly on or above the other layer or the other element. Further layers and / or elements can then be arranged between the one and the other layer or between the one and the other element.

The fact that a layer or an element is arranged “between” two other layers or elements can mean here and below that the one layer or the one element is in direct mechanical and / or electrical contact or in indirect contact with one of the other two Layers or elements and is arranged in direct mechanical and / or electrical contact or in indirect contact with the other of the two other layers or elements. In the case of indirect contact, further layers and / or elements can then be arranged between the one and at least one of the two other layers or between the one and at least one of the two other elements.

The heating element is preferably a conductor track which functions as resistance heating during operation of the laser diode chip. In particular, in the The heating element converts electrical energy into heat and the laser diode chip is specifically heated in this way. By means of the heating element, the laser diode chip can advantageously be specifically heated to a predetermined temperature at which the laser diode chip has a predetermined emission wavelength. In this way it is advantageously achieved that the laser diode chip has a stabilized emission wavelength.

In accordance with at least one embodiment, the laser diode chip is arranged on a heat sink, the active layer being arranged between the heating element and the heat sink. In other words, in this embodiment, the heating element is opposite the heat sink when viewed from the active layer. This enables a particularly efficient heating of the active layer by the heating element, since the heat paths between the heating element and the heat sink in this case run through the active layer and advantageously no parasitic heat paths exist. In this embodiment, in particular the n-type semiconductor region of the laser diode chip faces the heat sink, for example the n-type semiconductor region can be connected to the heat sink by means of a connection layer such as a solder layer. In this case, the heating element is arranged in particular on the side of the laser diode chip facing the surrounding medium. The heat sink is advantageously formed from a thermally highly conductive material such as copper.

In a preferred embodiment, the heating element and the p-contact of the laser diode chip have the same material. The manufacturing cost of the heating element is advantageously low in this case, since no layer made of an additional material has to be applied. In particular, the same coating method and / or the same structuring method can be used for producing the heating element as for producing the p-contact. The heating element preferably has at least one of the metals gold, titanium, platinum and palladium.

In accordance with at least one embodiment, the heating element is not provided for injecting an operating current into the active layer of the laser diode chip. In this way, the heating element differs in particular from the p-contact of the laser diode chip, which can consist of the same material as the heating element.

In a preferred embodiment, the heating element is connected to electrical contacts which are not connected to a p-contact or an n-contact of the laser diode chip. The circuits for the heating element and the laser diode chip are completely separated in this case. The current flow through the heating element can thus be regulated independently of the current flow through the active layer.

In an alternative embodiment, the heating element has a common contact with the laser diode chip. The common contact is preferably the p-contact of the laser diode chip. This common contact can be used to regulate the current flow through the laser diode chip and the heating element independently of one another when the laser diode chip and the heating element are operated simultaneously. To simplify the regulation, it is also possible to operate the laser diode chip and the heating element only alternately and not at the same time.

In accordance with at least one embodiment, the heating element is arranged above a p-contact of the laser diode chip, a passivation layer, for example a silicon oxide layer or a silicon nitride layer, being arranged between the heating element and the p-contact.

In one configuration, the laser diode chip has a ridge waveguide (ridge), the heating element being arranged parallel to the ridge waveguide. In this way, it is advantageously possible to uniformly heat the optically active region defined by the fin waveguide. The length of the heating element preferably corresponds essentially to the length of the fin waveguide.

In one configuration, the p-type semiconductor region is partially covered with a passivation layer, the heating element being arranged on the passivation layer. In this case, the heating element is advantageously separated from the p-type semiconductor region only by the passivation layer, so that the semiconductor material can be heated effectively.

In accordance with at least one embodiment, the heating element is formed, at least in regions, by a metallic seed layer. The metallic growth layer can have areas which are provided for the deposition of the p-contact. In this embodiment, the heating element is advantageously formed by a region of the growth layer, the growth layer being applied and structured anyway to produce the p-contact on the semiconductor layer sequence of the laser diode chip. The manufacturing outlay for producing the heating element is therefore advantageously low. The growth layer can have one or more metallic layers, for example a Ti / Pd / Au layer sequence or a Ti / Pt / Au layer sequence.

According to at least one embodiment, the heating element is a galvanic layer, at least in some areas. In this embodiment, the heating element is advantageously produced by galvanic deposition. A process for producing the heating element is therefore advantageously used, which is also advantageously used for producing the p-contact of the laser diode chip. This advantageously reduces the manufacturing outlay.

In accordance with at least one embodiment, a current path is formed through the p-type semiconductor region between the heating element and the p-contact of the laser diode chip. In this embodiment, the heating current can be supplied via a heating contact, which is electrically conductively connected to the p-type semiconductor region, and flows from there to the p-contact. In this way, an additional current path is generated in the p-type semiconductor region, which does not lead to the n-contact. The semiconductor material heats up due to the current flow along this current path, so that the p-type semiconductor region functions as a heating element. An advantage of this configuration is that the semiconductor material itself is heated directly. In this embodiment, the laser diode chip and the heating element are preferably not operated simultaneously. The laser diode chip and the heating element can be operated alternately, for example.

According to at least one embodiment, the heating element is connected to a control device which is set up to regulate the heating power of the heating element. The control device can in particular regulate a current flow through the heating element in order to set the heating power in this way. The control device can in particular be set up to regulate the heating power in such a way that the emission wavelength of the laser diode chip lies within a predetermined tolerance in a target value range.

The regulation can take place, for example, by directing at least part of the emitted radiation onto an optical filter which has a transmission window at the desired emission wavelength. In this case, the heating power of the heating element can be regulated in such a way that a detector element behind the optical filter detects a maximum intensity. If the wavelength of the emitted radiation changes, the heating power can be regulated in such a way that the intensity detected by the detector element is maximized.

The laser diode chip is described below using exemplary embodiments in connection with the 1 to 8th explained in more detail.

• 1A eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem ersten Beispiel,
• 1B eine schematische Darstellung einer perspektivischen Ansicht eines Laserdiodenchips gemäß dem ersten Beispiel,
• 1C eine Detailansicht des Laserdiodenchips gemäß dem ersten Beispiel,
• 2A und 2B jeweils beispielhafte Darstellungen der Stromkreise des Heizelements und des Laserdiodenchips,
• 3A eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem zweiten Beispiel,
• 3B eine schematische Darstellung einer perspektivischen Ansicht eines Laserdiodenchips gemäß dem zweiten Beispiel,
• 3C eine Detailansicht des Laserdiodenchips gemäß dem zweiten Beispiel,
• 3D eine weitere Detailansicht des Laserdiodenchips gemäß dem zweiten Beispiel,
• 4A eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem dritten Beispiel,
• 4B eine schematische Darstellung einer Draufsicht auf den Laserdiodenchip gemäß einem vierten Beispiel,
• 5 eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem fünften Beispiel,
• 6 eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem sechsten Beispiel,
• 7 eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem siebten Beispiel,
• 8 eine schematische Darstellung eines Querschnitts durch den Laserdiodenchip gemäß einem achten Beispiel.

Show it:

• 1A 1 shows a schematic representation of a cross section through the laser diode chip according to a first example,
• 1B 1 shows a schematic illustration of a perspective view of a laser diode chip according to the first example,
• 1C 2 shows a detailed view of the laser diode chip according to the first example,
• 2A and 2 B exemplary representations of the circuits of the heating element and the laser diode chip,
• 3A 2 shows a schematic representation of a cross section through the laser diode chip according to a second example,
• 3B 1 shows a schematic illustration of a perspective view of a laser diode chip according to the second example,
• 3C 2 shows a detailed view of the laser diode chip according to the second example,
• 3D 5 shows a further detailed view of the laser diode chip according to the second example,
• 4A 1 shows a schematic representation of a cross section through the laser diode chip according to a third example,
• 4B 1 shows a schematic illustration of a top view of the laser diode chip according to a fourth example,
• 5 1 shows a schematic representation of a cross section through the laser diode chip according to a fifth example,
• 6 1 shows a schematic representation of a cross section through the laser diode chip according to a sixth example,
• 7 2 shows a schematic representation of a cross section through the laser diode chip according to a seventh example,
• 8th is a schematic representation of a cross section through the laser diode chip according to an eighth example.

The same or equivalent components are provided with the same reference numerals in the figures. The components shown and the proportions of the components among one another are not to be considered as true to scale.

In the 1A . 1B and 1C An embodiment of the laser diode chip is shown in cross section, in a top view and in a detailed view of the top view. The laser diode chip has a semiconductor layer sequence 2 with an n-type semiconductor region 3 , an active layer 4 and ap type semiconductor region 5 on.

The active layer 4 can be designed, for example, as a pn junction, as a double heterostructure, as a single quantum well structure or as a multiple quantum well structure. The term quantum well structure encompasses any structure in which charge carriers experience a quantization of their energy states through confinement. In particular, the term quantum well structure contains no information about the dimensionality of the quantization. It includes quantum wells, quantum wires and quantum dots and any combination of these structures.

The semiconductor layer sequence 2 of the laser diode chip is preferably based on a III-V compound semiconductor material, in particular on an arsenide, nitride or phosphide compound semiconductor material. For example, the semiconductor layer sequence 2 In _x Al _y Ga _1-xy N, In _x Al _y Ga _1-xy P or In _x Al _y Ga _1-xy As, each with 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 and x + y ≤ 1, contain. The III-V compound semiconductor material does not necessarily have to have a mathematically exact composition according to one of the formulas above. Rather, it can have one or more dopants and additional constituents. For the sake of simplicity, however, the above formulas only contain the essential constituents of the crystal lattice, even if these can be replaced in part by small amounts of other substances. The material selection is based on the desired emission wavelengths of the laser diode chip.

In the p-type semiconductor area 5 is a ribbed waveguide 13 (ridge) trained. The rib waveguide 13 can be structured by structuring the p-type semiconductor region 5 , for example by a photolithographic process. The laser diode chip has an n-contact for electrical contacting 9 and ap contact 8th on, which are designed for example as metal layers.

The one on the p-type semiconductor area 5 arranged p-contact 8th can be, for example, a gold layer. The p contact 8th can in particular by galvanic deposition on a growth layer 7 getting produced. The thickness of the p-contact can be, for example, between 1 μm and 10 μm, in particular approximately 5 μm.

The growth layer 7 can be, for example, a titanium-palladium-gold layer sequence. The thickness of the growth layer 7 can be, for example, about 470 nm. In the exemplary embodiment, the p-contact 8th only on the top of the rib waveguide 13 with the p-type semiconductor area 5 electrically connected. Outside the rib waveguide 13 is the p contact 8th through a passivation layer 6 from the p-type semiconductor region 5 electrically isolated.

The laser diode chip has a p-type semiconductor region 5 facing side a heating element 14 on. In the embodiment shown here is the heating element 14 designed as a conductor track above the ribbed waveguide 13 and the p contact 8th is arranged. The heating element 14 is not electrically conductive with the p-contact in the present case 8th connected, but through a passivation layer 12 from the p-contact 8th isolated. The passivation layer 13 can for example be an oxide layer or nitride layer, in particular a silicon oxide layer or silicon nitride layer. The heating element designed as a conductor track 14 can like the p-contact 8 by electrodeposition of a metal layer 10 on a growth layer 11 getting produced. The metal layer 10 can be, for example, a gold layer. In that the heating element 14 The heating element can be made of the same material as the p-contact 8 and in particular can be produced with the same manufacturing method 14 can be realized with comparatively little production effort.

As in the top view in 1B can see the heating element 14 be designed as a conductor track, the length of which preferably essentially corresponds to the length of the rib waveguide 13 matches. In this way it can be achieved that the active layer 4 through the heating element 14 is heated evenly. The heating element 14 has an ohmic resistance, which results in particular from the length and the cross-sectional area of the heating element 14 results. The ohmic resistance, and thus the heating power or the current / voltage operating point, can be determined by the material, the layer thickness, the width and / or the length of the heating element 14 can be set. The layer thickness of the heating element 14 can be, for example, between 1 μm and 10 μm, in particular about 5 μm. The width of the heating element 14 is preferably between 5 microns and 30 microns.

The heating element 14 can have contact surfaces for electrical contacting at its ends. A heating power is generated by energizing the heating element, by means of which the semiconductor layer sequence 2 including the active layer 4 can be heated. The temperature-dependent emission wavelength of the laser diode chip can be specifically influenced by adjusting the heating power. It is advantageous that the heating element 14 directly above the semiconductor layer sequence 2 of the laser diode chip is arranged, in particular not on a carrier or a heat sink 1 of the laser diode chip. In this way, direct thermal contact with the semiconductor layer sequence can advantageously be achieved. The mass to be heated is therefore advantageously low. With the heating element described here 14 can therefore quickly and effectively regulate the temperature of the Semiconductor layer sequence and the temperature-dependent emission wavelength take place.

The laser diode chip is advantageous at the n-contact 9 with a heat sink 1 connected. In this case there is the light-emitting active layer 4 between the heating element 14 and the heat sink 1 , This enables efficient heating of the active layer 4 , since there are no parasitic heat paths between the heating element 14 and the heat sink 1 exist.

For the electrical connection of the heating element 14 In principle, two variants are conceivable 2A and 2 B are shown. 2A shows a variant in which the circuits for the laser diode chip and the heating element 14 are completely separate. For example, the heating element 14 two contacts h +, h-, which are separated from contacts p, n of the laser diode chip. This makes the control of the control simple, but requires four electrical contacts with corresponding effort in the contacting. The previously shown embodiment of the 1A to 1C shows such a variant.

As in 2 B shown, can alternatively a contact h of the heating element 14 be connected to a contact p of the laser diode chip, preferably the p-contact. This common contact can be used to control the current flow through the laser diode chip and the heating element 14 to be regulated independently of one another if the laser diode chip and the heating element 14 operated simultaneously. To simplify the regulation, it is also conceivable for the laser diode chip and the heating element 14 only operate alternately and not at the same time.

An embodiment of the laser diode chip, in which the heating element 14 and the laser diode chip have a common contact, is in the 3A to 3D shown. In this embodiment, the heating element 14 a part of a metal layer designed as a conductor track 8th . 10 which can have gold in particular. The metal layer 8th . 10 forms both the heating element in this example 14 as well as the p-contact 8th out. This has the advantage of producing the heating element 14 no further layers have to be applied and the manufacturing effort is therefore low. 3A shows a cross section through the laser diode chip. 3B shows how the heating element 14 is carried out by cutting out the metal layer as a conductor track. The detailed view in 3C shows a contact area 14a for the heating element 14 , As in the further detailed view in 3D to see is one end of the trace, which is the heating element 14 forms with the p-contact 8th connected.

4A shows in cross section a modification of the previous embodiment. The heating element 14 is in this example through the structured growth layer 11 educated. Because the growth layer 11 is thinner and has a higher resistivity than the metal layer which has the p-contact 8th trained, the ohmic resistance is otherwise higher than in the example of the same dimensions 3 , This enables other heating outputs and / or other current / voltage operating points to be implemented.

The two in the examples of 3A and 4A Cross sections shown can also alternate parallel to the longitudinal axis of the rib waveguide 13 Arrange. One such example is in 4B shown schematically in plan view. The cross section along the line AB corresponds to that in this example 4A and the cross section along the line CD the example of 3A , The heating element 14 in the longitudinal direction alternately comprises first areas in which only the growth layer 11 is present, and second areas in which an additional metal layer 10 on the growth layer 11 is applied. The metal layer 10 is, for example, a gold layer with a thickness of approximately 1 μm to 20 μm, in particular approximately 5 μm, which is preferably produced by electroplating. The metal layer 10 has in particular the same material as the p-contact 8 and can simultaneously with the p-contact 8th manufactured and structured. Through the first areas of the heating element 14 with the metal layer 10 the current can flow with less resistance, while in the second areas without a metal layer over the growth layer 11 the resistance is higher. The relationship between the first areas and the second areas is another design parameter with which the ohmic resistance of the heating element 14 can be adjusted.

The 5 and 6 show further modifications of the previous examples. In these examples, the heating element is 14 directly above the rib waveguide 13 arranged, but in contrast to 1 not above the p-contact 8. The operating current for the laser diode chip is supplied from the laterally arranged p-contact 8 via the growth layer 7 to the rib waveguide 13 , The growth layer 7 is in some areas of the p-type semiconductor area 5 through a passivation layer 6 , for example a silicon oxide layer or a silicon nitride layer, electrically insulated. On this growth layer 7 is in the area of the rib waveguide 13 another passivation layer 12 applied as electrical insulation. On the passivation layer 12 is a growth layer 11 arranged. The growth layer 11 can comprise, for example, titanium, platinum, palladium and / or gold, in particular the growth layer 11 have a Ti-Pd-Au or Ti-Pt-Au layer sequence.

In the embodiment of the 5 the growth layer acts 11 even as a heating element 14 , In this example in particular no further metal layer is arranged over the growth layer. The heating element is advantageous over the fin waveguide 13 arranged so that the heating power reaches the radiation-emitting active layer particularly effectively. The heating element 14 is therefore close to the rib waveguide 13 and on that of the heat sink 1 opposite side arranged. In comparison to 1 there is no heat spread through the p-contact 8th and the associated losses in heating power. Compared to the examples of 3 and 4 parasitic heat paths through the semiconductor material and the associated losses in heating power are eliminated.

In the embodiment of the 6 the growth layer acts 11 with an applied metal layer 10 as a heating element 14 , The metal layer 10 is, for example, a gold layer with a thickness of approximately 1 μm to 20 μm, in particular approximately 5 μm, which is preferably produced by electroplating. The metal layer 10 has in particular the same material as the p-contact 8 and can be produced and structured simultaneously with the p-contact 8.

As with the previous example of the 4B is also in the examples of 5 and 6 one in the longitudinal direction of the heating element 14 alternating arrangement of first areas, in which only the growth layer 11 is present, and second areas in which a metal layer 10 on the growth layer 11 is applied, conceivable.

7 shows another way the heating element 14 close to the rib waveguide 13 to place. In this embodiment is on the growth layer 7 that are used to grow the p-contact 8th serves a passivation layer 12 applied. On the passivation layer 12 is a structured, conductive growth layer 11 as a heating element 14 arranged. The growth layer 11 is, for example, a titanium-platinum-gold layer sequence. Heating elements designed in this way 14 extend on both sides into the recess next to the rib waveguide 13 , The heating power is thus closer to the fin waveguide 13 introduced than in the execution after 4A ,

In addition, in 7 shown that the heating elements 14 advantageous on both sides and symmetrical to the ribbed waveguide 13 can be attached. The advantage is that such a symmetrical temperature distribution in the fin waveguide 13 can be achieved. This prevents the beam profile or the distribution of the laser modes of the laser diode chip from becoming asymmetrical. The symmetrical arrangement of the heating elements 14 is also conceivable in the embodiments according to the 3 and 4A ,

8th shows a further embodiment of the laser diode chip. In this example is the heating element 14 not a structure of the layers applied to the semiconductor material, but the semiconductor material itself. The heating current is generated via a heating contact, in particular a metal layer 10 , is supplied and flows from there to the p-contact 8. In this way, the p-type semiconductor region 5 in addition to the current path 16 by the active layer 4 leads to n-contact 9, another current path 15 generated that does not lead to the n-contact. Through the flow of electricity along this current path 15 the semiconductor material heats up, so the p-type semiconductor region 5 acts as a heating element. The advantage of this embodiment is, on the one hand, that the semiconductor material itself is heated directly, and, on the other hand, that no fine structuring of the layers is necessary 9 flows. One possibility is that the heating element 14 and the laser diode chip, as described above, cannot be operated simultaneously.

All of the exemplary embodiments described above are distinguished by the fact that the additional outlay in the production of the laser diode chip is only slight, since the heating elements 14 can each be realized with materials that are applied anyway in the manufacture of the laser diode chip. Also affect the heating elements 14 the performance data of the laser diode chip is not or only to a small extent, so that the laser diode chips have no disadvantages compared to identical laser diode chips without heating elements.

Due to the low mass to be heated, low heating capacities are necessary for the active layer 4 bring to the target temperature and thus stabilize the wavelength. This also enables high heating rates in order to achieve a quick adjustment of the wavelength. Due to the low mass, faster cooling rates are achieved when the laser diode chip is thermally connected to a heat sink 1 is connected. This enables an agile regulation of the temperature and thus the emission wavelength.

Regulation of the emission wavelength can also be used to compensate for any production-related scatter in the wavelength of several laser diode chips, by regulating the temperature of the laser diode chip as a function of the wavelength so that the laser emits at the desired wavelength.

If the heating element 14 of the laser diode chip is used to regulate the emission wavelength, the regulation can take place, for example, by directing at least part of the emitted radiation onto an optical filter which has a transmission window at the desired emission wavelength. In other words, the optical filter is a narrow-band filter that is only transparent in a narrow wavelength range around the desired emission wavelength. In this case, the heating power of the heating element can be regulated in such a way that a detector element behind the narrow-band optical filter detects a maximum intensity. If the wavelength of the emitted radiation changes, the heating power can be regulated in such a way that the intensity detected by the detector element is maximized.

The invention is not limited by the description based on the exemplary embodiments. Rather, the invention encompasses every new feature and every combination of features, which in particular includes every combination of features in the patent claims, even if this feature or this combination itself is not explicitly specified in the patent claims or exemplary embodiments.

LIST OF REFERENCE NUMBERS

1

heat sink

2

Semiconductor layer sequence

3

n-type semiconductor area

4

active layer

5

p-type semiconductor area

6

passivation

7

Anwachsschicht

8th

p-contact

9

n-contact

10

metal layer

11

Anwachsschicht

12

passivation

13

Ridge waveguide

14

heating element

14a

contact area

15

current path

16

current path

Claims (15)

Laser diode chip, comprising - an n-type semiconductor region (3), a p-type semiconductor region (5) and an active layer (4) arranged between the n-type semiconductor region (3) and the p-type semiconductor region (5), an n-contact ( 9) and a p-contact (8), - At least one heating element (14), which are arranged on a side of the laser diode chip facing the p-type semiconductor region (5), the heating element (14) functioning as resistance heating. Laser diode chip after Claim 1 , wherein the heating element (14) is a conductor track (10, 11). Laser diode chip according to one of the preceding claims, wherein the laser diode chip is arranged on a heat sink (1), and wherein the active layer between the heating element (14) and the heat sink (1) is arranged. Laser diode chip according to one of the preceding claims, wherein the heating element (14) and the p-contact (8) have the same material. Laser diode chip according to one of the preceding claims, wherein the heating element (14) comprises at least one of the metals gold, titanium, platinum or palladium. Laser diode chip according to one of the preceding claims, wherein the heating element (14) is connected to electrical contacts which are not connected to the p-contact (8) or the n-contact (9) of the laser diode chip. Laser diode chip according to one of the Claims 1 to 6 , wherein the heating element (14) has a common contact with the laser diode chip. Laser diode chip according to one of the preceding claims, wherein the heating element (14) is arranged above the p-contact (8) of the laser diode chip, a passivation layer (12) being arranged between the heating element (14) and the p-contact (8). Laser diode chip according to one of the preceding claims, wherein the laser diode chip has a ribbed waveguide (13), and wherein the heating element (14) is arranged parallel to the ribbed waveguide (13). Laser diode chip according to one of the preceding claims, wherein the p-type semiconductor region (5) is partially covered with a passivation layer (6), and wherein the heating element (14) is arranged on the passivation layer (6). Laser diode chip according to one of the preceding claims, wherein the heating element (14) is at least partially formed by a metallic growth layer (11), wherein the p-contact (8) is partially deposited on the metallic growth layer (11). Laser diode chip according to one of the preceding claims, wherein the heating element (14) has a galvanic layer. Laser diode chip according to one of the preceding claims, in which a current path through the p-type semiconductor region (5) is formed between the heating element (14) and the p-type contact (8). Laser diode chip according to one of the preceding claims, wherein the heating element (14) is connected to a control device which is set up to regulate the heating power of the heating element (14). Laser diode chip after Claim 14 , in which the control device is set up to regulate the heating power in such a way that an emission wavelength lies within a predetermined tolerance in a target value range.

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